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       <title>??</title>
       <style type="text/css">
          *{margin:0;padding:0;}
           #layer1{width:100%; height:200px;}
           #layer1-1{width:33.33%; height:200px; background:red;text-align:center;float:left;}  
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           #layer1-4{clear:both;} 
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           #layer3{width:100%; height:200px;  background:red;color:white;text-align:center;}           
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    <body>
       <div id="layer1">
          <div id="layer1-1"></div>
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          <div id="layer1-3"></div>
          <div id="layer1-4"></div>
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       <div id="layer2">
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       <div id="layer3">?</div>
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